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51.
Alan A Arslan Anne Zeleniuch-Jacquotte Annekatrin Lukanova Yelena Afanasyeva Joseph Katz Mortimer Levitz Giuseppe Del Priore Paolo Toniolo 《Cancer epidemiology, biomarkers & prevention》2006,15(11):2123-2130
Epidemiologic evidence suggests that a full-term pregnancy may affect maternal risk of breast cancer later in life. The objective of this cross-sectional study was to compare circulating levels of maternal hormones affecting breast differentiation (human chorionic gonadotropin and prolactin) and proliferation [alpha-fetoprotein, insulin-like growth factor I (IGF-I), and estradiol] between women at a low to moderate risk (Asians and Hispanics), as compared with women at a high risk for breast cancer (Caucasians and African-Americans). Between May 2002 and December 2004, a total of 586 pregnant women were approached during a routine prenatal visit. Among them, 450 women (206 Caucasian, 126 Asian, 88 Hispanic, and 30 African-American) met the inclusion criteria and signed the informed consent. Only singleton pregnancies were considered. Blood samples were drawn during the second trimester of pregnancy. Laboratory analyses were done using the IMMULITE 2000 immunoassay system. Gestational age standardized mean levels of estradiol, IGF-I, and prolactin were significantly higher in Hispanic women compared with Caucasian women. Mean concentration of IGF-I was significantly higher in African-American women compared with Caucasian and Asian women. No significant differences in pregnancy hormone levels were observed between Caucasian and Asian (predominantly second-generation Chinese) women in this study. Irrespective of ethnicity, women who had their first pregnancy had substantially higher mean levels of alpha-fetoprotein, human chorionic gonadotropin, estradiol, and prolactin compared with women who previously had at least one full-term pregnancy. These data suggest that circulating pregnancy hormone levels may explain some of the ethnic differences in breast cancer risk. 相似文献
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54.
José I. Bilbao Manuel Ruza Jesús M. Longo Francisco Mansilla Antonio Picardi Vanessa de Villa Fernando Pardo Jesús Sola Jorge Quiroga 《Cardiovascular and interventional radiology》1994,17(4):210-213
Posttransplant lymphoproliferative disorders are infrequent tumors related to chronic immunosuppressive therapy. We present a liver transplant recipient who developed such a tumor in the porta hepatis that provoked obstruction of the entire portal triad. Treatment consisted of systemic chemotherapy, percutaneous dilatation, and placement of Wallstent endoprostheses across both biliary and portal vein stenoses. The patient died 3 weeks later of pneumonia and sepsis. At necropsy, the tumor was completely necrosed and the prostheses in both the common bile duct and the portal vein were patent. 相似文献
55.
J I Bilbao J M Longo A Martín-Palanca L Mu?oz-Galindo 《Journal of vascular and interventional radiology : JVIR》1992,3(3):553-555
Two cases are presented in which conventional approaches did not permit dilation of and stent placement in obstructed ureters. In patients with iatrogenic ureteral laceration or rigid ureteral kinking, direct percutaneous translumbar puncture may provide a safe alternative. The authors' technique is described. 相似文献
56.
B Rotoli A Camera R Fontana F Frigeri G Pandolfi R Vecchione V Poggi G Longo C Carestia M De Angioletti 《Haematologica》1992,77(2):110-118
BACKGROUND. Structural hemoglobinopathies usually are inherited as autosomic dominant traits; de novo mutations are uncommon. Analytical and preparative procedures for the characterization of an abnormal hemoglobin are complex and time-consuming. Mass spectrometer analysis allows a rapid identification of the amino acid substitution. METHODS AND RESULTS. A cyanotic 7-year-old girl was found to have 16% methemoglobin. Laboratory data showed the presence of an abnormal hemoglobin, which was isolated by collecting the abnormal peak from DEAE and globin chains from CM52. The amino acid substitution was rapidly identified by FAB mass spectroscopic analysis, leading to the recognition of HbM Hyde Park. These data were confirmed by molecular analysis (Southern blot and DNA sequencing). Neither the parents nor a sister showed any abnormality; non-paternity was excluded by blood group serology and HLA typing. CONCLUSIONS. This is a case of HbM Hyde-Park arising as a de novo mutation. FAB mass spectroscopic analysis is a rapid and useful analytical method for identifying aminoacid substitution. 相似文献
57.
Mono- and bi-allelic expression of insulin-like growth factor II gene in human muscle tumors 总被引:4,自引:1,他引:3
Pedone Paolo V.; Tirabosco Roberto; Cavazzana Andrea O.; Ungaro Paola; Basso Giuseppe; Luksch Roberto; Carli Modesto; Bruni Carmelo B.; Frunzio Rodolfo; Riccio Andrea 《Human molecular genetics》1994,3(7):1117-1121
Insulin-like growth factor II (IGF-II) is a mitogen for manycell types and an important modulator of muscle growth and differentiation.IGF-II gene is prevalently expressed during prenatal developmentand its gene activity is regulated by genomic imprinting, inthat the allele inherited from the father is active and theallele inherited from the mother is inactive in most normaltissues. IGF-II expression is activated in several types ofhuman neoplasms and an alteration of IGF-II imprinting has beendescribed in BeckwithWiedemann syndrome and Wilms' tumour.Here we show that monoallelic expression of IGF-II gene is conservedin normal adult muscle tissue whereas two or more copies ofactive IGF-II alleles, arising by either relaxation of imprintingor duplication of the active allele, are found in 9 out of 11(82%) rhabdomyo-sarcomas retaining heterozygosity at 11p15,regardless of the histological subtype. Since IGF-II has beenindicated as an autocrine growth factor for rhabdomyosarcomacells, these findings strongly suggest that acquisition of adouble dosage of active IGF-II gene is an important step forthe initiation or progression of rhabdomyosarcoma tumorigenesis.Among different types of muscle tumors, relaxation of imprintingseems to arise prevalently in rhabdomyosarcomas, since we havedetected only one case of partial reactivation of the maternalIGF-II allele out of 7 lelomyosarcomas tested. 相似文献
58.
59.
Angelo Pan Placido Mondello Klara Posfay-Barbe Patrizia Catenazzi Annise Grandi Silvia Lorenzotti Andrea Patroni Nadia Poli Laura Soavi Giuseppe Carnevale 《Infection control and hospital epidemiology》2007,28(9):1099-1102
In an Italian hospital, we observed that hand hygiene was performed in 638 (19.6%) of 3,253 opportunities, whereas gloves were worn in 538 (44.2%) 1,218 of opportunities. We observed an inverse correlation between the intensity of care and the rate of hand hygiene compliance (R2=0.057; P<.001), but no such association was observed for the rate of glove use compliance (R2=0.014; P=.078). Rates of compliance with hand hygiene and glove use recommendations follow different behavioral patterns. 相似文献
60.
Pedro Moral Elisabetta Marini Esther Estebanup Giuseppa Elisa Mameli Valeria Succa Giuseppe Vona 《American journal of human biology》2002,14(1):21-28
Four communities from Guahibo of Venezuela were analyzed for the genetic variants of nine erythrocyte enzymes and five serum proteins. Of the 14 loci determined, four were monomorphic. Significant frequency differentiation among communities, was present for ESD and TF markers. In general, Guahibo allele frequencies are in the variation ranges described for South American groups. The analysis indicates a relatively higher affinity of Guahibos with other Venezuelan groups within an irregular pattern of genetic distances that are likely related to the complex demographic history of the South American groups. Genetic diversity estimates reveal a moderate degree of genetic structure between the four Guahibo communities. This intra‐tribal variability in Guahibo appears to be lower than in Venezuelan Piaroa but higher than in other Amerindians and could be attributed to a combined effect of low population size and relative isolation of communities. At a continental level, the distribution of genetic diversity is consistent with preferential population movements along the eastern and western coastal areas. Am. J. Hum. Biol. 14:21–28, 2002. © 2002 Wiley‐Liss, Inc. 相似文献